The present invention provides a unitary diverter/bypass valve which controls the flow of a fluid through a secondary flow path.
A typical situation in which a valve system is required to perform diversion and bypass functions is found in solar heating of swimming pools. Water drawn from the pool and filtered is diverted to a solar collector when solar heating is available and useful before passing through a conventional heater and returned to the pool. If the water already is as hot as desired, or if solar energy is not available, the solar collector is simply bypassed.
In conventional systems employing solar heating of swimming pools, a relatively complex and expensive valve system is required to control diversion to the solar collector. A first control valve is used to divert the water to the collector and isolate the collector, if desired, and a second control valve is used to bypass the collector. At least two check valves are also required, one to prevent backflow to the filter unit, and one to prevent flow to the collector in the bypass mode. The primary deterent to the use of solar energy is usually cost, and the additional expense of such a complex valving system is a significant barrier to the widespread use of solar heating in swimming pools. Also, such extra plumbing significantly increases the pumping pressure required to move the water through the system.